pneumonia is immunocompromised individuals Flashcards
what is the most common cause of pneumonia in immunocompromised individuals?
Caused by Pneumocystis jirovecii pneumonia (PCP)
how does in PCpneumonia arise?
inhalation of fungus
pneumonia arises from re-infection rather than reactivation of persisting organisms acquired in childhood
in a normal immune system there is asymptomatic carriage or eradication
what are the clinical features of PCP?
high fever dry cough SOB fatigue in HIV individuals sub acute, low grade fever> severe pneumonia non HIV more acute, higher fever A characteristic feature on examination is rapid desaturation on exercise or exertion
what would a CXR for PCP show?
typical:
- diffuse bilateral alveolar and interstitial shadowing beginning in the perihilar regions and spreading out like a butterfly
what other investigations wuold be done for PCP?
bronchoalveolar lavage > sputum> gargle
microscopy : immunofluorescence
PCR
what is the treatment for PCP?
first line - cotrimoxazole
pentamidine
what other infection of the lung is common in immunocompromised individuals ?
aspergillus infection - a fungal chest infection
what common environmental fungus causes the aspergillus infection
aspergillus fumigatus
what does aspergillus cause in immunocompromised individuals?
severe pneumonia and invasive disease
what doe aspergillus cause in normal people
causes localised pulmonary infection
-aspergilloma (fungus ball) in pre-existing chest cavities
what do the pre-existing cavities mean ?
in people who have had TB, the aspergillus can get into the cavities
how is aspergillus infection diagnosed?
BAL then do a fungal culture and PCR
could look at histopathology of tissue
